San Justo in Summer
In summer (December, January and February), San Justo sees average daytime highs around 30°C and overnight lows near 19°C, with 383 mm of rain over about 27 wet days across the season. It is the warmest season of the year and the wettest season of the year.
Across summer, daytime highs hold fairly steady around 30°C. The sky is clear or mostly clear about 48% of the time across summer, and the air most often feels muggy.
Summer is San Justo's weakest season of the year to visit on our travel score. For the whole year in context, see San Justo's year-round climate.
- Avg daytime high
- 30°C
- warmest season of the year
- Avg overnight low
- 19°C
- Rainfall
- 383 mm
- 27 wet days
- Avg wind
- 11 km/h
- Travel score
- 5.0
- weakest season of the year
- Months
- Dec · Jan · Feb
Temperature in San Justo in Summer
Across summer, daytime highs hold fairly steady around 30°C.
A typical summer day in San Justo reaches about 30°C and drops to 19°C overnight. The warmest of the three months is January, the coolest December.
How summer really feels in San Justo
Once humidity and wind are folded in, summer brings about 31 days that feel above 32°C and 0 that feel at or below 0°C.
The story in summer is heat — humidity pushes the afternoon "feels like" well above the raw temperature.
San Justo weather by month
How the three summer months (December, January and February) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 31° / 20° | 125 | 9.6 | 13.8 | 4.6 |
| Feb | 30° / 20° | 124 | 8.7 | 13.1 | 5.2 |
| Mar | 28° / 18° | 126 | 8.9 | 12.2 | 6.3 |
| Apr | 25° / 15° | 132 | 8.9 | 11.3 | 7.2 |
| May | 21° / 12° | 78 | 6.2 | 10.5 | 7.1 |
| Jun | 18° / 9° | 49 | 5.2 | 10 | 6.7 |
| Jul | 18° / 8° | 37 | 4.3 | 10.2 | 6.9 |
| Aug | 21° / 9° | 56 | 4.7 | 10.9 | 7.5 |
| Sep | 23° / 11° | 70 | 6.3 | 11.8 | 7.6 |
| Oct | 25° / 14° | 137 | 9.2 | 12.8 | 7.1 |
| Nov | 28° / 16° | 125 | 8.1 | 13.6 | 6.6 |
| Dec | 30° / 19° | 134 | 8.9 | 14 | 5.3 |
Cloud cover in Summer
The sky is clear or mostly clear about 48% of the time across summer.
Chance of precipitation in Summer
San Justo gets around 383 mm of rain over 27 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels muggy — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 11 km/h across summer.
Sunrise & sunset in Summer
Daylight runs from about 13 h 54 min in early December to 12 h 42 min by late February. The lit band spans sunrise to sunset each day.
Solar energy in Summer
Average shortwave solar energy reaching the ground each day across summer, about 6.8 kWh/m².
Is summer a good time to visit San Justo?
Our two travel scores rate summer for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
summer is a reasonable time to visit San Justo for sightseeing. The water and warmth also suit a beach or pool day.
What to pack for San Justo in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, San Justo sees daytime highs around 30°C and nights near 19°C. Pack light clothes and sun protection. Worth having: rain gear. About 27 days see rain.
UV index in San Justo in Summer
Clear-sky midday UV across summer averages around 13 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in San Justo peaks around January 18 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 20 at about 3 (moderate).
The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 14 | 13 | 10 | 7 | 4 | 3 | 4 | 5 | 7 | 9 | 11 | 13 |
| Level | Extreme | Extreme | Extreme | High | Moderate | Moderate | Moderate | Moderate | High | Very high | Extreme | Extreme |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 14 | Extreme |
| Feb | 13 | Extreme |
| Mar | 10 | Extreme |
| Apr | 7 | High |
| May | 4 | Moderate |
| Jun | 3 | Moderate |
| Jul | 4 | Moderate |
| Aug | 5 | Moderate |
| Sep | 7 | High |
| Oct | 9 | Very high |
| Nov | 11 | Extreme |
| Dec | 13 | Extreme |
Where is San Justo?
San Justo sits at 30.8°S, 60.6°W, 49 m above sea level, in Argentina. The nearest listed city is San Javier, 68 km away.
Topography around San Justo
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of San Justo.
Within 3 km, the terrain around San Justo has only modest variations in elevation — a maximum elevation change of 26 m around an average of 52 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 49 m; within 80 km, only modest variations in elevation — a maximum elevation change of 79 m.
The land around San Justo is covered by cropland (55%) and grassland (23%) within 3 km, cropland (72%) and grassland (20%) within 16 km, and cropland (41%) and grassland (30%) within 80 km.
Argentina travel facts
- Travel advisory
- Level 1
- Exercise Normal Precautions
- Power plugs
- Type C / I
- 220 V · 50 Hz
- Prices
- ≈ 46% of US
- price level, 2025
- GDP per capita
- $14,898
- 2025
- Happiness
- 6.4 / 10
- World Happiness, 2025
- Homicide rate
- 4.5
- per 100k, 2023
- Road deaths
- 14.1
- per 100k/yr, 2019
- Income group
- Upper middle
- World Bank
- English
- High
- EF EPI 575
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for San Justo (-30.7899°, -60.5928°, elevation 49 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google.